The present invention relates to an improved anchor for securing laparoscopic instruments within puncture opening during surgery. In its more specific aspects, the invention is concerned with a balloon anchor adapted to be secured to the outside surface of virtually any laparoscopic instrument, without the necessity of modifying the structure of the instrument.
Laparoscopic surgery provides a minimally invasive approach to a wide variety of surgical procedures in, for example, the abdominal and thoracic cavities. In a minimally invasive approach, small incisions are made to provide access for instruments needed to perform surgery. The instruments, such as trocars, endoscopes, clip appliers, cautery devices and other tools, are commonly inserted through these small incisions using cannulas which are adapted to provide a pressure seal when using pneumoperitoneum. It is desirable to secure or anchor these cannulas into position in the incision to allow easy insertion and withdrawal of instruments through the cannula without corresponding movement of the cannula. Likewise, it is sometimes desirable to secure or anchor an instrument itself in an incision and prevent unwanted distal or proximal movement of the instrument.
Prior anchors for laparoscopic instruments have employed threaded sleeves adapted to be secured to the instruments and screwed into a laparoscopic puncture opening to secure the instrument in place. An anchor of this type is found in U.S. Patent No. 5,217,441. Such anchors require a specific size for each size of instrument, since the sleeve must be of a configuration complemental to that of the instrument. The screw threads also must be twisted into place and are relatively traumatic.
The prior art also teaches adhesive anchors, sometimes called “grippers,” for securing laparoscopic instruments in place within puncture openings. Such anchors employ a tubular boss configured to snugly engage the instrument and a flexible disk carried by the boss for adhesion to the outside surface of the punctured tissue. The boss must be specifically configured to match the configuration of the instrument being anchored. Blood emitting from the puncture opening often intrudes between the disk and the tissue so as to destroy the integrity of the anchor during surgery.
The prior art also teaches the provision of specially constructed laparoscopic cannula provided with inflatable balloons to anchor the cannula in place within a puncture opening. A cannula of this type may be seen in U.S. Pat. No. 5,002,557. Such cannula are expensive to fabricate and must be especially configured to match the instrument with which they are used.
It is also old in the art to anchor drainage catheters with balloons incorporated into the catheter. One well-known catheter of this type used for urinary drainage is the “Foley” catheter. In such catheters, the balloon and the conduit provided for its inflation is integrally molded into the catheter.